Using two commercially available breast cancer cell lines obtained from women with estrogen-receptor-positive breast cancer, the research team exposed the cancer cells to varying strengths of BPS or to an inactive substance as a control.

“We also treated the breast cancer cells with estradiol (estrogen) and found that BPS acted like estrogen in multiplying breast cancer cells,” said Sumi Dinda of Oakland University."

Compared with the control, BPS heightened the protein expression in estrogen receptor and BRCA1 after 24 hours, as did estrogen," says Dinda."

After a six-day treatment with BPS, the breast cancer cells in both cell lines reportedly increased in number by 12 per cent at the lowest dose (four micromolars) and by 60 per cent at eight micromolars," he added.